This invention relates to discrete fastener regions, and more particularly to fastener elements, capable of engaging a material, extending from discrete regions of a base or substrate.
Fastener products having a base substrate with fastener elements for engagement with loops or like fastener elements can be continuously produced from, e.g., a thermoplastic material. Typically, methods for producing such fastener products result in tape-like substrates having a continuous pattern of fastener elements extending across an entire surface or in uniform bands or rows along the length of the substrate. Often times, however, it would be advantageous in applications for such fastener products, to have the presence of the fastener elements limited to pre-selected zones or arranged in patterned areas along the substrate.
For example, there are some applications where it would be desirable to have patterned fastener element, e.g., hook, areas with adjacent areas that lack fastener element protrusions on a common web. Currently any such fastener products are generally made by multi-step forming, cutting and joining operations because most hook products are limited to complete or at least continuous hook coverage across or along the length of the hook bearing web. Providing hook products having other configurations would generally require specially designed tooling, e.g., hook forming mold cavity rolls with flat areas and hook forming cavity areas in the desired configuration. However, if the desired hook bearing shape and/or pattern were subsequently changed, the specialty tool would require redesign and or rebuilding to accommodate the change.
In an aspect, a method of making a fastener product having discrete regions of fastener element stems extending from a section of a strip-form base is provided. The method includes: providing a gap formed along a peripheral surface of a rotating mold roll; the mold roll having a plurality of cavities extending from the peripheral surface; positioning a compliant sleeve about the mold roll, the sleeve covering select ones of the plurality of cavities; continuously introducing molten resin to the gap such that the resin forms at least a part of the strip-form base of the product at the peripheral mold roll surface and at least partially fills a plurality of the cavities and the aperture, while the resin remains blocked from said selective ones of the cavities by the sleeve, to form fastener element stems as projections extending from the section, the section extending from the strip form base, the sleeve compressing under pressure in the gap; solidifying the resin; and stripping the solidified resin from the peripheral surface of the mold roll by pulling the projections from their cavities.
In another aspect, a method of making a fastener product having discrete regions of fastener element stems extending from a base includes: providing a gap formed along a peripheral surface of a rotating mold roll, the mold roll having an array of cavities extending from the peripheral surface; positioning a sleeve about the mold roll, the sleeve having an outer surface and an inner surface and defining at least one aperture extending between the inner and outer surfaces to expose a region of the array of cavities, the aperture intersecting the inner surface of the sleeve at an inner opening that is smaller than an outer opening of the aperture at the outer sleeve surface; introducing the sleeve to the gap; continuously introducing molten resin to the gap such that the resin forms at least a part of the strip-form base of the product at the peripheral mold roll surface and at least partially fills the region of the array of cavities and the aperture to form fastener element stems as projections extending from an upper surface of a plateau, the plateau molded integrally with and extending from the base and the upper surface of the plateau is smaller in area than an overall area of the base covered by the plateau; solidifying the resin; and stripping the solidified resin from the peripheral surface of the mold roll by pulling the projections from their cavities.
Some embodiments include a compliant sleeve. In some cases the sleeve resiliently compresses, (i.e, the sleeve has an elastic property allowing portions of the sleeve, following compression, to at least substantially assume its original, uncompressed configuration once outside a pressure region, for example, once outside the gap region). In some embodiments, the compliant sleeve is resiliently expanded about the mold roll. This expansion allows for positioning of the mold roll sleeve about the mold roll.
Some embodiments include a mold roll sleeve having an aperture that includes a chamfered or a radiused edge. Chamfered or radiused edges of the aperture form a fastener product having a corresponding chamfered or radiused edge.
In some versions, the cavities of the mold roll comprise a number of shapes allowing for the formation of a variety of projections. For example, the cavities can be stem-shaped thus forming projections extending from the section to a distal tip of the projection. The distal tips of the projections can then be post-formed, including deforming the distal tips to form loop-engaging heads on the projections. In some embodiments, the cavities include a loop-engaging head shape thus forming projections with loop-engaging heads. The loop-engaging head shapes can be hooks, for example.
Some embodiments also include introducing a backing material to the molten resin while the resin is disposed in the gap. The backing material can be a nonwoven, printable cloth, plastic film, a resiliently extensible material, paper, woven fabric or the like, as examples.
In another aspect, a fastener product includes a planar base, multiple discrete plateaus molded integrally with and extending from an upper surface of the base each plateau having an upper surface that is smaller in area than an overall area of the base covered by the plateau, and an array of discrete fastener elements integrally molded with and extending from the upper surface of the plateau.
In another aspect, a fastener product includes a base comprising a first material, a plateau molded integrally with and extending from the base and having an upper surface that is smaller in area than an overall area of the base covered by the plateau, the plateau having at least one layer comprising a second material, and an array of fastener elements integrally molded with and extending from the upper surface of the plateau.
Various embodiments include fastener elements of different shapes including hook-shapes and/or mushroom-shapes, for example. In some embodiments, the plateaus include a radiused and/or a chamfered edge allowing for a relatively smooth transition from a surface of the base to an upper surface of the plateau. An advantage of this smooth transition, among others, is that the radiused or chamfered edge provides a softer xe2x80x9cfeelxe2x80x9d for a user coming in contact with a surface of the fastener product.